Air driven turbopump



Aug. 30, 1966 J. H. TWEET 3,269,117

AIR DRIVEN TURBOPUMP Filed June 28, 1965 2 Sheets-Sheet 1 Aug. 30, 1966 .1. H. TWEET 3,269,117

AIR DRIVEN TURBOPUMP Filed June 28, 1965 2 Sheets-Sheet 2 United States Patent Office 3,Z69',1 l7 Patented August 30, 1966 3,269,117 AIR DRIWEN TURBQPUMP John H. Tweet, Tolland, Conn., assignor to the United States of America as represented by the Secretary of the Air Force Filed June 28, 1965, Ser. No. 467,796 3 Claims. (Cl. oil-39.18)

This invention relates to an air-turbine-driven accessory package for turbojet engines.

One object of the invention is to provide a fuel pump, water pump, oil pump, on a single shaft with seal means to prevent mixing of the fluids and which provide a greater freedom of location and mounting arrangement for the assembly than prior art devices.

Another object of the invention is to provide an accessory package for turbojet engines which have less Weight than prior art devices, which require no gears, is less complicated, and thus more reliable.

A further object of the invention is to provide an accessory package for turbojet engines in which the pumping speed is independent of the engine speed.

These and other objects will be more fully understood from the following detailed description taken with the drawing, wherein:

FIG. 1 is a schematic diagram showing how the accessory packages of a turbojet engine is supplied with compressor bleed air;

FIG. 2 is a longitudinal sectional view of the accessory package of FIG. 1; and

FIG. 3 is a left end view of the accessory package of FIG. 2 showing the injector nozzles.

Reference is now made to FIG. 1 of the drawing which shows an air turbine accessory package located adjacent a turbojet engine 11. The accessory drive turbine 12 is driven by compressor bleed air from engine 11 through duct 14. A control valve in the duct 14 controls the air flow to the accessory driven turbine 12 and therefore controls the speed of turbine 12. Valve 15 is controlled by the output of the fuel metering computer, not shown. The accessory drive turbine 12 supplies power to drive oil pump 16, fuel pump 17 and water pump 18. The output of the fuel pump 17 is fed to fuel control 19'. A portion of the output is fed to injectors in the inlet through line 20 to increase the fuel pump suction pressure.

To reduce the weight of the ducting, necessary to ex haust the air from the accessory drive turbine 12 into the engine exhaust nozzle, a separate exhaust 21 is provided for the accessory drive turbine.

As shown in FIG. 2, the water impeller 22, the oil impeller 23, and fuel impeller 24, are all driven by a common shaft 25 and an auxiliary shaft 25a splined to shaft 25. The shaft 25 is driven by the turbine drive 26.

A water pump 22 is a standard centrifugal water pump. A baffle 27 and slinger 28 are provided to keep Water from reaching the turbine and bearings. Water from water supply tank, not shown, is fed to inlet port 29 with the output being taken off at 31. Back vanes 30 are provided on the impeller 22 to aid in keeping water out of the turbine and bearings. A drain 32 is provided for water from the slinger 28. Cooling water for the engine turbine 13 is taken off at outlet port 31.

A labyrinth seal 34 is provided between the turbine drive 26 and the bearing compartment 35 to reduce the air load on the carbon ring seal 36. The inner labyrinth is vented through a screened vent 38.

The oil impeller 23 is a standard drill hole pump consisting of a rotating drum 39 with a plurality of drilled holes 49 therein. Selection of the size and angle of the holes determines the pressure rise in the pump. Inlet and outlet passages for the oil pump are shown at 42 and 43 which lead to ports not shown. Carbon face seals 44 and 45 are provided on each side of the oil pump to prevent static oil leakage from the oil pump into the turbine bearing compartments 46 and 47. Oil for the turbine bearings 49 and 5% is provided by bearing jets 52 and 53.

The fuel pump 17 is a conventional centrifugal pump. A fuel injector 54 consisting of six nozzles 55 is provided in the input 56 of the fuel pump to raise the fuel pump suction pressure available at the impeller inlet. A part of the fuel from the pump discharge is returned to the pump inlet through injector nozzles 55 through inlet 57, as shown schematically in FIG. 1. The remainder of the fuel from the pump outlet 58 is passed through the main fuel control for the turbojet engine.

In the operation of the accessory package, compressor bleed air from the compressor 69 drives the accessory turbine drive 26 Which is secured to shaft 25. This, in turn, drives the water pump impeller 22, the oil impeller 23 and fuel impeller 24. A port-ion of the fuel impeller output is fed to the fuel impeller input through nozzles to increase the net positive suction head available at the impeller inlet. Since all of the accessory equipment is driven from a single shaft, special sealing means is provided between the fuel compartment 61, oil compartment 62, turbine compartment 63, and water pump compartment 64- to prevent mixing of the different fluids.

There is thus provided an accessory package which is light in weight, which requires no gears, and wherein there is greater freedom of location of the accessories than in prior art devices.

While a certain specific embodiment has been described, it is obvious that numerous changes can he made without departing from the general principle and scope of the invention.

I claim:

1. An air driven turbine accessory package for a turbojet engine having a compressor, burners, and turbine drive; comprising: a housing for said accessory package including, a fuel pump compartment with input and output ports, an oil pump compartment with input and output passages, a turbine drive compartment and a water pump compartment with input and output ports; a pair of bearings supported within said housing, with one bearing on each side of said oil compartment; means within said housing for supplying oil to said bearings; a drive shaft passing through each of said compartments and supported by said bearings; a turbine drive, in said turbine drive compartment, connected to said shaft; duct means, adapted to be connected to the compressor of said turbojet engine for supplying air to said turbine drive; means, connected in said duct means, for controlling the flow of air to said turbine drive, whereby the speed of said turbine drive can be controlled; a centrifugal water pump impeller, in said water pump compartment, connected to one end of said drive shaft adjacent said turbine drive; means for keeping water from said water pump compartment from entering said turbine drive compartment; a centrifugal drill hole oil pump drum, in said oil pump compartment, connected to said drive shaft; means for keeping oil from said pump compartment from reaching said bearings; a fuel impeller connected to said drive shaft at the end remote from said water pump; means for preventing mixing of fuel and oil in said fuel pump compartment and around said bearings; a plurality of injector nozzles adjacent the input of said fuel impeller and means for supplying a portion of the output fuel from said fuel impeller to said nozzles to raise the fuel pump suction pressure.

2. An air driven turbine accessory package for a turbojet engine having a compressor, burners, and turbine drive;

comprising: a housing for said accessory package including, a fuel pump compartment, with an input and an output port, an oil pump compartment with input and output passages, a turbine drive compartment and a water pump compartment with input and output ports; a pair of bearings supported within said housing, with one bearing on each side of said oil compartment; jet means within said housing, for supplying oil to said bearings; a drive shaft passing through each of said compartments and supported by said bearings; a turbine drive, in said turbine drive compartment, connected to said shaft; duct means, adapted to be connected to the compressor of said turbojet engine for supplying air to said turbine drive; means, connected in said duct means, for controlling the flow of air to said turbine drive, whereby the speed of said turbine drive can be controlled; a centrifugal water pump impeller, in said water pump compartment, connected to one end of said drive shaft adjacent said turbine drive; means for keeping water from said water pump compartment from entering said turbine drive compartment; a centrifugal drill hole oil pump drum, in said oil pump compartment, connected to said drive shaft; a first and second radial projection on said drive shaft between said pump compartment and said bearings; a face seal supported by said housing adjacent and contacting said radial projections, for keeping oil from said pump compartment from reaching said bearings; a fuel impeller connected to said drive shaft at the end remote from said water pump; a third radial projection on said drive shaft between said fuel impeller and said bearings; a face seal supported by said housing adjacent and contacting said third radial projection for preventing mixing of fuel and oil in said fuel pump compartment and around said bearings; a plurality of injector nozzles adjacent the input of said fuel impeller and means for supplying a portion of the output fuel from said fuel impeller to said nozzles to raise the fuel pump suction pressure.

3. An air driven turbine accessory package for a turbojet engine having a compressor, burners, and turbine drive; comprising: a housing for said accessory package including, a fuel pump compartment with input and output ports, an oil pump compartment with input and output passages, a turbine drive compartment and a water pump compartment with input and output ports; a pair of bearings supported within said housing, with one bearing on each side of said oil compartment; jet means within said housing for supplying oil to said bearings; a drive shaft passing through each of said compartments and supported by said bearings; a turbine drive, in said turbine drive compartment, connected to said shaft; a labyrinth seal between said turbine drive and the housing for the bearing on the side of said oil pump adjacent said turbine drive; duct means, adapted to be connected to the compressor of said turbojet engine for supplying air to said turbine drive; means, connected in said duct means, for controlling the flow of air to said turbine drive, whereby the speed of said turbine driven can be controlled; a centrifugal water pump impeller, in said water pump compartment, connected to one end of said drive shaft adjacent said turbine drive; said water pump impeller having back vanes for keeping water from flowing into said turbine compartment; slinger and baffle means for aiding in keeping Water from said water pump compartment from entering said turbine drive compartment; a centrifugal drill hole oil pump drum, in said oil pump compartment, connected to said drive shaft; a first and second radial projection on said drive shaft between said pump compartment and said bearings; a face seal adjacent and contacting said radial projections, for keeping oil from said pump compartment from reaching said bearings; a fuel impeller connected to said drive shaft at the end remote from said water pump; a third radial projection on said drive shaft between said fuel impeller and said bearings; a face seal adjacent and contacting said third radial projection for preventing mixing of fuel and oil in said fuel pump compartment and around said bearings; a plurality of injector nozzles adjacent the input of said fuel impeller and means for supplying a portion of the output fuel from said fuel impeller to said nozzles to raise the fuel pump suction pressure.

References Cited by the Examiner UNITED STATES PATENTS 2,612,757 10/1952 Teague 60-57 2,806,351 9/1957 Kent. 2,840,986 7/1958 Davies.

MARK NEWMAN, Primary Examiner.

R. D. BLAKESLEE, Assistant Examiner. 

1. AN AIR DRIVEN TURBINE ACCESSORY PACKAGE FOR A TURBOJET ENGINE HAVING A COMPRESSOR, BURNERS, AND TURBINE DRIVE; COMPRISING: A HOUSING FOR SAID ACCESSORY PACKAGE INCLUDING, A FUEL PUMP COMPARTMENT WITH INPUT AND OUTPUT PORTS, AN OIL PUMP COMPARTMENT WITH INPUT AND OUTPUT PASSAGES, A TURBINE DRIVE COMPARTMENT AND A WATER PUMP COMPARTMENT WITH INPUT AND OUTPUT PORTS; A PAIR OF BEARING SUPPORTED WITHIN SAID HOUSING, WITH ONE BEARING ON EACH SIDE OF SAID OIL COMPARTMENT; MEANS WITHIN SAID HOUSING FOR SUPPLYING OIL TO SID BEARINGS, A DRIVE SHAFT PASSING THROUGH EACH OF SAID COMPARTMENTS AND SUPPORTED BY SAID BEARINGS; A TURBINE DRIVE, IN SAID TURBINE DRIVE COMPARTMENT CONNECTED TO SAID SHAFT; DUCT MEANS, ADAPTED TO BE CONNECTED TO THE COMPRESSOR OF SID TURBOJET ENGINE FOR SUPPLYING AIR TO SAID TURBINER DRIVE; MEANS, CONNECTED IN SAID DUCT MEANS, FOR CONTROLLING THE FLOW OF AIR TO SAID TURBINE DRIVE, WHEREBY THE SPEED OF SAID TURBINE DRIVE CAN BE CON- 